Dragline hoist attachement

ABSTRACT

A dragline hoist attachment is provided to increase the speed at which the dragline is reeled in during back-casting operations. A friction wheel is provided engageable with the clutch rim of the dragline hoist drum, and which is rotated at a peripheral speed much higher than the normal peripheral speed of the clutch rim. Means are provided to engage this friction wheel with the clutch rim as the bucket is swinging toward the cab, reeling in the slack at a relatively high rate.

lnventor Appl. No. Filed Patented DRAGLINE HOIST ATTACHEMENT Delbert J. Kirk Willernie, Minn. 55090 Sept. 28, 11971 [56] lileierencm Cited UNITED STATES PATENTS 1,639,151 8/1927 Sommer Primary Examiner-Even C. Blunk Assistant Examiner-Alfred N. Goodman Attorney-Robert M. Dunning ABSTRACT: A dragline hoist attachment is provided to increase the speed at which the dragline is reeled in during back- 4clalms7nrawing Figs casting operations. A friction wheel is provided engageable ILLS. Cl 254/187, with the clutch rim of the dragline hoist drum, and which is 74/665, 254/185 rotated at a peripheral speed much higher than the normal Int. Cl 366d 1/24 peripheral speed of the clutch rim. Means are provided to enlField of Search 254/149, gage this friction wheel with the clutch rim as the bucket is 192/4 high rate.

swinging toward the cab, reeling in the slack at a relatively PATENTEU SEP28 ism SHEET 1 BF 2 INVENTOR UMBER?" d, Km

ATTORNEY PATENTEU 8EP28 1am SHEET 2 [1F 2 INVENTOR ATTORNEY DRAGLINE IIOIST A'I'IACHEMENT This invention relates to an improvement in dragline hoist attachment and deals particularly with an attachment to a device of the type described which simplifies the task of back casting during dragline operations.

In the operation of a dragline hoist, it is often necessary to fill up the dragline bucket by drawing the bucket toward the hoist. The material collected in the bucket is then released at a greater distance from the hoist by allowing the bucket to swing outwardly like a pendulum and then releasing the contents. One of the problems in this operation lies in the fact that after the bucket has been dumped, the bucket swings back toward the cab of the hoist device at a speed which is considerably greater than the speed at which the dragline may be reeled in. As a result, the control of the bucket is lost until the slack in the hoisting cable is taken up so that the operation may again be controlled.

I have found that the speed of operation of the device may be substantially doubled by providing an auxiliary drive member which may be used to speed up the rotation of the drag hoist drum during the time the hoist is reeling in the slack cable and while the bucket is swinging toward the hoist. With this arrangement, the necessity for waiting for the hoist drum to reel in the slack cable is eliminated, greatly increasing the speed of the hoisting operation.

An object of the present invention resides in the provision of an auxiliary drive which may be powered from the same power supply as the hoisting drums, or which may be powered by separate power supply, and which is capable of rotating the dragline hoist drum at an increased rate of speed during the time the drag bucket is swinging toward the hoist, and which may be readily disconnected at other times. In the preferred arrangement, a friction wheel is provided which is supported closely adjacent to the drag line hoist clutch so that it may be frictionally engaged with the peripheral rim of the clutch. An expandable and contractable cylinder is provided for swinging the friction wheel into and out of engagement with the clutch rim. When the auxiliary drive means is engaged with the clutch rim, the drag hoist drum is normally disconnected from the usual power source and the drum is rotated at a relatively high speed, serving to reel in the dragline and to thereby eliminate most of the slack which normally occurs in certain back-casting operations. When the slack has been properly reeled in, the auxiliary power means is disengaged from the clutch rim, and the hoist is operated in the usual manner.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claims.

In the drawings forming a part of the specification:

FIG. 1 is a top plan view of a portion of a dragline hoist, showing a hoisting drum and a dragline drum, clutches for operating the drums, and the auxiliary dragline drum operating mechanism.

FIG. 2 is a sectional detail showing one manner in which the auxiliary power may be driven.

FIG. 3 illustrates diagrammatically the manner in which the auxiliary drive means may engage the clutch rim of the dragline drum.

FIG. 4 is a diagrammatic view of the auxiliary drive apparatus.

FIG. 5 is a sectional view through the friction wheel.

FIG. 6 is a sectional view through the auxiliary drive clutch mechanism, the position of the section being indicated by the line 6-6 of FIG. 5.

FIG. 7 is an enlarged view of the friction drive wheel and the cylinder for urging the drive wheel into or out of engagement with the rim of the clutch.

In view of the fact that hoisting equipment has been produced for a great number of years, the structure is not shown in its entirety. The frame of the device is indicated in general by the numeral 10, and bearings 11 are provided which support a shaft 12. A large diameter gear 13 on the shaft 12 is driven by a drive pinion 14 from a suitable engine. A hoist drum 15 is mounted upon the shaft 12 and may be connected thereto by a clutch which is indicated at 16. The dragline hoist drum or drag line drum 17 is also mounted upon the shaft 12 and may be connected thereto through a clutch l9. Suitable means are provided, not shown in the drawings, for engaging the clutches l6 and I9 so as to drive the drums l5 and 17 by the gear 13. Suitable brakes are also usually provided encircling portions of the clutches, and by means of which the rotation of the drums may be stopped.

A pair of upright frame members 20 and 18 are provided on opposite sides of the frame I0, and support a fixed shaft 21 extending across the frame in generally parallel relation to the axis of the shaft 12. An auxiliary drive mechanism which is indicated in general by the numeral 22 is supported by the frame. This auxiliary drive mechanism is perhaps best illustrated in its entirety in FIG. 4 of the drawings. As indicated in this FIG., the frame member 20 supports a bracket plate 23 which supports a pair of aligned bearings 24 rotatably supporting a shaft 25. A pinion 26 is mounted upon the shaft 25 and is in mesh with the large-diameter gear 13 for rotation thereby. In the particular arrangement illustrated, the shaft 25 is continuously driven whenever the large-diameter gear 113 is in rotation.

As is indicated in FIGS. 1 and 7 of the drawings, an angle iron member 27 is welded or otherwise secured to the fixed shaft 21. A bracket plate 29 (see FIG. 7) is pivotally connected to the bracket 27 as indicated at 30. An arm 31 is welded or otherwise secured to the angle member 27 and extends upwardly therefrom. As shown in FIG. 4, the bracket plate 29 supports a pair of axially spaced bearings 32 which support a shaft 33 on an axis substantially parallel to the axis of the hoisting drums. The shafts 25 and 33 are substantially aligned. An intermediate shaft 34 connects the shafts 25 and 33, one end of the intermediate shaft 34 being connected through a universal joint 35 to the shaft 25, and the other end of the intermediate shaft 34 being connected to the shaft 33 through a second universal joint 36. Thus the shaft 33 is constantly rotated when the hoist is in operation.

A friction wheel 37 is mounted upon the shaft 33. As indicated in FIG. 5 of the drawings, a disc 38 is keyed or bolted to the shaft 33 as indicated at 39. A brake drum 41 is secured to the center flange 42 of the friction wheel 37 by means of bolts 43 or other suitable means. A lbrake band 40 encircles the brake drum and is supported by the disc 38. As indicated in FIG. 6 of the drawings, one end of the brake band 40 is dead-ended to a pin 44 mounted upon the disc 38. The other end of the brake drum 40 is supported by a bolt 45 extending through and into the band and through a lug 46 on the disc 38. A springe 47 holds the band 40 slightly loosely when the drum 41 is traveling in the direction of the arrow 49 in FIG. 6. However, relative rotation in the opposite direction tightens the brake band against the drum 411 and permits a certain amount of slippage. The arrangement is such that a certain amount of slippage may take place, taking the strain off the various parts.

Bracket means 50 are provided on the plate 29 and act to support a cylinder 51 connected to a fluid supply line such as 52. A piston rod 53 forming a part of the cylinder 51 is pivotally connected at 54 to the arm 31. When air is introduced into the cylinder 51, the expansion of the cylinder swings the plate 29 in a clockwise direction about the axis of its pivot 30, forcing the friction wheel 37 against the rim 55 of the clutch 19. In other words, the cylinder 51 provides a virtually instantaneous means of engaging and disengaging the wheel from the clutch drum.

The operation of the device is generally as follows. The device is particularly useful during the process of back-casting with the drag line. The pinion being a relatively small diameter, rotates at a high relative speed. The friction wheel 37 is rotated through the shafts connected to the pinion 26 and is normally supported in the slightly spaced relation to the rim 55 of the clutch 19.

During the back casting operation, the bucket is drawn relatively near to the hoist, and the drag cable released while the bucket is supported much nearer the cab then the point of support. As a result, the bucket swings outwardly like a pendulum to the extent of its movement. At this point, the bucket is usually emptied. As the bucket reaches the extent of its movement, and starts to swing backwardly to the cab, the cylinder 51 is actuated, and the friction wheel is engaged with the clutch rim of the clutch 19. This causes rapidrotation of the drag line drum 17 in a direction to wind up the cable upon the drum. Normally the drum 17 rotates so slowly that considerable time is required to take up the slack, and it is necessary for the operator to merely wait till the dragline slack has been removed so that the bucket may again be drawn toward the cab. With the present attachment, the drag line is reeled in at about the same speed the bucket is swinging toward the cab, and as a result, approximately one-half of the time in the drag line operations may be saved. This is extremely important, as the equipment is extremely costly; and speeding up the operation results in substantial savings from an economic standpoint. However, the present device also appears to provide the operator with better control due to the fact that the slack is removed from the drag line.

In the foregoing description, a particular form of construction has been described as this type of construction and has been produced and has been found to be very effective. However, it should be understood that the power supply arrangement could be varied quite materially on difl'erent forms of equipment. For example, in place of driving the friction wheel from the main drive gear of the device, a hydraulic motor or similar type of power drive may be used to rotate the friction wheel. The main purpose of the present device is to provide an auxiliary drive means which is capable of functioning to rotate the drag line drum at an increased speed during back-casting operations so that the slack in the drag line is mainly removed as the bucked swings toward the cab.

l have described the principles of construction and operation of my improvement in dragline hoist attachment, and while I have attempted to set forth the best embodiment thereof, I desire to have it understood that obvious changes may be made within the scope of the following claims without departing from the spirit of my invention.

l claim:

1. A dragline hoist attachment in combination with a hoist having a drive shaft, a dragline hoist drum on said drive shaft, and clutch means for connecting said drive shaft to said drum, said clutch means including a member having a peripheral rim rotatable with said drum, said attachment including:

a friction wheel,

means for supporting said friction wheel for movement into and out of engagement with said rim, and

means for rotating said friction wheel in a drum winding direction at a peripheral speed substantially greater than the peripheral speed of said rim when clutch engages said drum to said shaft,

said drive shaft, including a concentric drive gear,

said means for rotating said friction wheel including a pinion engaging said drive gear, and shaft means connect ing said pinion and said friction wheel.

2. A dragline hoist attachment in combination with a hoist having a drive shafi, a dragline hoist drum on said drive shaft, and clutch means for connecting said drive shaft to said drum, said clutch means including a member having a peripheral rim rotatable with said drum, said attachment including:

a friction wheel,

means for supporting said friction wheel for movement into and out of engagement with said rim, and

means for rotating said friction wheel in a drum winding direction at a peripheral speed substantially greater than the peripheral speed of said rim when clutch engages said drum to said shaft,

said supporting means including a supporting shaft, and

overrunning clutch means connecting said friction wheel to said last named shaft.

3. The structure of claim 1 and in which said means connecting said pinion and said friction wheel includes a first shaft supported in parallel relation to said drive shaft upon which said pinion.

4. A dragline hoist attachment in combination with a hoist having a drive shaft, a dragline hoist drum on said drive shaft, and clutch means for connecting said drive shaft to said drum, said clutch means including a member having a peripheral rim rotatable with said drum, said attachment including:

a friction wheel,

means for supporting said friction wheel for movement into and out of engagement with said rim, and

means for rotating said friction wheel in a drum winding direction at peripheral speed substantially greater than the peripheral speed of said rim when clutch engages said drum to said shaft,

said means supporting said friction wheel includes supporting shaft, and slip clutch means permitting free rotation in one direction but retarding rotation in the opposite direction connecting said friction wheel to said lastnamed shaft. 

1. A dragline hoist attachment in combination with a hoist having a drive shaft, a dragline hoist drum on said drive shaft, and clutch means for connecting said drive shaft to said drum, said clutch means including a member having a peripheral rim rotatable with said drum, said attachment including: a friction wheel, means for supporting said friction wHeel for movement into and out of engagement with said rim, and means for rotating said friction wheel in a drum winding direction at a peripheral speed substantially greater than the peripheral speed of said rim when clutch engages said drum to said shaft, said drive shaft, including a concentric drive gear, said means for rotating said friction wheel including a pinion engaging said drive gear, and shaft means connecting said pinion and said friction wheel.
 2. A dragline hoist attachment in combination with a hoist having a drive shaft, a dragline hoist drum on said drive shaft, and clutch means for connecting said drive shaft to said drum, said clutch means including a member having a peripheral rim rotatable with said drum, said attachment including: a friction wheel, means for supporting said friction wheel for movement into and out of engagement with said rim, and means for rotating said friction wheel in a drum winding direction at a peripheral speed substantially greater than the peripheral speed of said rim when clutch engages said drum to said shaft, said supporting means including a supporting shaft, and overrunning clutch means connecting said friction wheel to said last named shaft.
 3. The structure of claim 1 and in which said means connecting said pinion and said friction wheel includes a first shaft supported in parallel relation to said drive shaft upon which said pinion.
 4. A dragline hoist attachment in combination with a hoist having a drive shaft, a dragline hoist drum on said drive shaft, and clutch means for connecting said drive shaft to said drum, said clutch means including a member having a peripheral rim rotatable with said drum, said attachment including: a friction wheel, means for supporting said friction wheel for movement into and out of engagement with said rim, and means for rotating said friction wheel in a drum winding direction at a peripheral speed substantially greater than the peripheral speed of said rim when clutch engages said drum to said shaft, said means supporting said friction wheel includes supporting shaft, and slip clutch means permitting free rotation in one direction but retarding rotation in the opposite direction connecting said friction wheel to said last-named shaft. 